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\usepackage{amsfonts}
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\usepackage{amsmath,amssymb,amsfonts}
\usepackage{color,xcolor}
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\usepackage{amsthm}

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%\newtheorem{proposition}{Proposition}
\newtheorem{proposition}{命题}
\newtheorem{theorem}{定理}
\newtheorem{definition}{定义}
\newtheorem{example}{例}

\renewcommand\figurename{图}
\renewcommand\tablename{表}

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\begin{document}

\title[ss]{ss}
\author[ss]{马}
\institute[math] {数学系}
\date[April, 2014]{2014~年~4~月}
\frame{\titlepage}

\begin{frame}
\frametitle{问题背景}
sss
\end{frame}

\end{document}